The invention relates to a machine comprising at least two working chambers with variable volume volume and at least one inlet opening and one outlet opening for gaseous or liquid media.
The field of use of the machine according to the invention includes the fields of internal-combustion engines, steam engines or machines or pressure-operated engines or machines (by gases or liquids or fluids) and the areas of use of pumps for gaseous and liquid media.
In conventional internal-combustion engines (piston engines) an oscillating movement of the pistons is converted into a rotary movement of the crankshaft. A disadvantage of these internal-combustion engines is the fact that valves, a crankshaft and a camshaft must be present. Since an oscillating movement of parts always involves a retardation and acceleration of masses, which firstly reduces the efficiency and secondly leads to an increased stress of the components of the engine, so-called rotary piston engines were developed which have only rotating parts.
Like the reciprocating piston engines, these rotary piston engines have sealed working chambers with rigid walls, at least one of which is moved in such a manner that a variable volume of the working space results. The variable working space or chamber is formed between the power member (that is, the piston transmitting the power) and the shutoff part not transmitting any power. Rotary piston engines are subdivided into rotational piston, orbiting piston and revolving piston engines.
A disadvantage of rotational piston engines and orbital piston engines is that their mass forces must be compensated externally by counterweights. In a rotational piston engine, because of the rotating shutoff member, the supply of the fresh gas and discharge of the waste gases is difficult. For this reason, of rotary piston engines only the Wankel engine operating on the principle of an orbital piston engine has established itself. However, the major problem in a Wankel engine is the satisfactory sealing of the working chambers. Further disadvantages reside in that only about 6% of the total volume is available as useful volume for the working chambers, that due to the rotation of the Wankel disc the engine is unbalanced, and that for the power transmission a crankshaft and additional gears are likewise necessary.
Further disadvantages in a reciprocating piston engine are that when the engine is operated the heat arising in the pistons must be dissipated via piston rings of small cross-section because the cylinder diameter cannot be adapted when thermal dimensional changes take place.
Also, with respect to sealing in the Wankel engine, first sealing strips are required at the corners of the rotary piston, and second sealing elements are necessary at the side faces of the rotary piston because the spacing of the side walls cannot be varied. In both cases the sealing elements offer large resistance to heat dissipation, and consequently the cooling of the pistons or of the rotor cannot be as effective as is desired.